2. Difference between Postgres Pro Enterprise and PostgreSQL
Postgres Pro provides the most actual PostgreSQL
version with some additional patches applied and extensions added.
It includes new features developed by Postgres Professional,
as well as third-party patches already accepted by the PostgreSQL community
for the upcoming PostgreSQL versions.
Postgres Pro Enterprise users thus have early access
to important features and fixes.
Postgres Pro Enterprise provides the following enhancements
over PostgreSQL:
- 64-bit transaction IDs that are not subject to wraparound.
(See Section 24.1.5.)
- Page-level compression. (See Chapter 33.)
- Support for autonomous transactions. (See Chapter 16.)
- Lazy placement of temporary tables on disk.
Disk space for temporary tables is allocated only when they
exceed the temp_buffers size and have to be
spilled to disk. Since disk space for temporary tables is not
reserved in advance anymore, it allows to significantly reduce
disk usage when working with multiple small temporary tables.
-
Resource prioritization experimental feature, which allows to
allocate more resources to high-priority sessions.
(See Section 18.4.6.)
-
Automatic page repair via streaming replication from standby
in case of data corruption. (See Section 26.2.5.3.)
-
Fair lightweight lock scheduling after the specified number of
shared locks is acquired. (See lwlock_shared_limit
parameter description.)
-
Controlling the amount of cache used by prepared statements.
With plan_cache_lru_size or
plan_cache_lru_memsize configuration
parameters enabled, query trees and generic plans of
the least recently used statements are evicted from cache once
the specified limit is reached.
-
Improved prioritization of sequential and index scans.
(See seq_scan_startup_cost_first_row parameter description.)
-
Improved multi-host connection handling and failover
by libpq. (See hostorder
and failover_timeout parameter descriptions.)
-
Enabling libpq to forget the entered password,
which allows to prevent reconnections when required by a security policy.
(See reusepass parameter description.)
-
Support for timestamp output in pg_waldump.
-
Support for relaxed synchronous replication restrictions, which allows
the primary server to continue running while some of the standbys are temporarily unavailable.
(See synchronous_standby_gap parameter description.)
-
Built-in connection pooler that can limit the
number of backends when working with multiple clients, without
imposing restrictions on using session configuration parameters,
prepared statements, or temporary tables.
(See Chapter 34 for details.)
-
The autoprepare mode that allows to implicitly prepare
frequently used statements, thus eliminating the cost of their compilation
and planning on each subsequent execution. (See Section 14.6.)
-
Support for changing configuration of other sessions.
For example, you can use this feature to switch on debug
messages to trace sessions with unexpected behavior.
(See Section 9.27.1.)
- K-nearest neighbors (k-NN) algorithm for B-tree indexes.
(See Section 11.13.)
-
Removing a practically reachable limit on the number of entries
in ACL (access control list, i.e., privileges list) associated
with tables and indexes.
-
The pgpro_stat_wal_activity view that shows
the size of WAL files generated by each process.
-
Restoration of corrupted WAL data from in-memory WAL buffers.
-
Verification of unique constraints in B-tree indexes in the
amcheck module.
-
Login event triggers, which fire
when a user connects to the database after authentication. For example, you can use
this feature to verify the connection and assign roles according to circumstances,
or for session data initialization.
-
Support for packages, which are essentially enhanced schemas
that help to organize named objects with a related purpose.
This feature provides extended functionality, familiar to Oracle
users, for PL/pgSQL where new
function modifiers and
conventions were introduced, as well as new
CREATE PACKAGE
and DROP PACKAGE
commands.
-
Support for passing named and positional arguments to scripts invoked
by the
\i command in
psql.
-
pg_probackup
enterprise edition, which provides Simple Storage Service (S3) support
for storing data in private clouds,
CFS (Compressed File System) support
for incremental backups, and support for lz4 and zstd
compression algorithms.
-
Lock deduplication that allows to effectively store in memory
and track all exclusive locks held by a standby server's startup process
during WAL replay.
The following enhancements are inherited from
Postgres Pro Standard:
- Improved deadlock detection mechanism that does not cause performance degradation.
-
Better planning speed and accuracy for various query types.
-
Reduced memory consumption in complex queries that involve multiple tables.
-
Displaying planning time in the output of the
auto_explain module.
NUL byte replacement with the specified ASCII code while
loading data using the COPY FROM command. (See
nul_byte_replacement_on_import parameter
description.)
'\u0000' character replacement with the specified
unicode character when calling a function processing JSONB (See
unicode_nul_character_replacement_in_jsonb parameter
description.)
- PTRACK implementation, which enables pg_probackup
to track page changes on the fly when creating incremental backups.
-
Support for reading
pg_control of previous
PostgreSQL/Postgres Pro major
versions by pgpro_controldata.
-
Cluster compatibility verification, which allows you to determine whether the
current Postgres Pro version is compatible with
the specified cluster and identify all parameters that can affect
the compatibility without starting the cluster.
(See pgpro_controldata and
-Z option of postgres.)
-
Changing the
restore_command
parameter without restarting the server.
-
Unified structure of binary installation packages across all
Linux distributions, which facilitates migration between them and
allows to install different PostgreSQL-based
products side by side, without any conflicts. (See Chapter 17.)
-
Operation log, which stores information about system events such as an
upgrade, execution of pg_resetwal and so on,
which is highly useful for vendor's technical support. Recording to the
operation log is only done at the system level, and SQL functions are
used to read it. (See Section 9.27.12.)
-
Advanced authentication policies that provide effective password management and access control.
(See CREATE PROFILE and ALTER ROLE).
-
Built-in data security mechanisms that enable sanitizing an object
by filling it with zeroes before deletion. Zeroing can be done before
purging files in external memory and removing outdated row versions (page vacuum),
freeing RAM, and deleting or overwriting WAL files. (Certified edition only.)
-
Pilot implementation of SQL/JSON standard, including JSON constructor
and SQL/JSON query functions,
IS JSON predicates, and
JSON_TABLE function. (See Section 9.16.3.)
-
Collection of statistics about vacuuming tables and indexes.
The collected information is displayed by pgpro_stats and
pgpro_pwr.
Postgres Pro Enterprise also includes the
following additional modules:
- aqo extension for adaptive query optimization.
- dump_stat module that allows
to save and restore database statistics when dumping/restoring the database.
- fasttrun module
that provides transaction-unsafe function to truncate temporary tables
without growing
pg_class size. - fulleq module that
provides additional equivalence operator for compatibility with Microsoft SQL Server.
- hunspell-dict module that provides
dictionaries for several languages.
-
in_memory module
that enables you to store data in Postgres Pro shared memory.
- jsquery module that
provides a specific language for effective index-supported querying of JSONB data.
- mamonsu monitoring service, which
is implemented as a Zabbix agent.
- mchar module that provides
additional data type for compatibility with Microsoft SQL Server.
- multimaster extension
that turns Postgres Pro Enterprise into a synchronous shared-nothing
cluster to provide Online Transaction Processing (OLTP) scalability for read
transactions and high availability with automatic disaster recovery.
- online_analyze
module that provides a set of changes to immediately update statistics after
INSERT, UPDATE, DELETE
or SELECT INTO operations applied for affected tables. - pgbouncer connection pooler.
- pg_hint_plan
module that controls the execution plan by providing hints to the planner.
- pg_integrity_check
module that calculates and validates checksums for controlled files. (Certified edition only.)
-
pg_pathman module that
provides optimized partitioning mechanism and functions to manage partitions, as well as
declarative syntax.
Starting from Postgres Pro 12, using
pg_pathman is not recommended. Use vanilla
declarative partitioning instead, as described in
Section 5.11.
-
pg_proaudit extension that enables detailed
logging of various security events.
-
pgpro_anonymizer
extension that provides the ability to mask or replace personally
identifiable information or commercially sensitive data
from a Postgres Pro database.
-
pgpro_application_info
extension designed to help developers who port applications
using the
DBMS_APPLICATION_INFO package
from Oracle to Postgres Pro.
- pg_probackup, a backup and recovery manager.
- pgpro_controldata, an application to
display control information of a
PostgreSQL/Postgres Pro
database cluster and compatibility information for a
cluster and/or server.
- pgpro_pwr extension that enables you
to generate workload reports, which help to discover most resource-intensive activities in your database.
- pgpro_scheduler module that provides background workers for task scheduling.
- pgpro_stats extension that tracks execution statistics
of SQL statements, calculates wait event statistics and provides other useful
metrics that are not collected elsewhere in PostgreSQL.
It also provides tracing of application sessions and can create views that emulate
other statistic collecting extensions.
- pg_query_state
module that enables you to get the current state of query execution for a backend.
- pg_repack
utility for reorganizing tables.
- pg_transfer module that provides support for relocatable tables.
- pg_tsparser module,
which is an alternative text search parser.
- pg_variables module
that provides functions for working with variables of various types.
-
pg_wait_sampling
extension for sampling-based statistics of wait events. With this extension,
you can get an insight into the server activity, including the current wait
events for all processes and background workers.
- plantuner
module that provides hints for the planner to disable or enable indexes for query execution.
- rum module that
provides RUM index based on GIN.
- shared_ispell
module that enables storing dictionaries in shared memory.
- sr_plan
experimental extension that allows the user to save a specific
plan of a parameterized query for future usage regardless of how
planner settings may change.
-
vops experimental module
that provides a vertical data model for Postgres Pro Enterprise.
It can speed up OLAP queries with filtering and aggregation by times.
To provide the advanced functionalities and features, Postgres Pro
imposes more stringent requirements on operating systems supported.
Important
Postgres Pro Enterprise runs on all major Linux operating systems.
Any reference to Windows or another operating system different from Linux in this documentation
is inapplicable for Postgres Pro.
Postgres Pro Enterprise releases follow PostgreSQL releases, though sometimes occur more frequently.
The Postgres Pro Enterprise versioning scheme is based on the PostgreSQL one and has an additional decimal place.